The Mountain Arapesh of New Guinea lived in small camps or hamlets grouped into ceremonial communities, which in turn formed larger groupings called localities. During the 1930s, population density was 20 people/sq kilometer, plus or minus five. The nucleation index was .86, where 0 is equivalent to complete nucleation and 1 represents complete randomness. Data gathered on the Mountain Arapesh by Margaret Mead and Reo Fortune in 1931-32 was marred by inconsistent use of Western terms such as 'village' and 'hamlet' to describe Mountain Arapesh settlements. Additional data was collected in 1991.